Taplow firecrest
Hearing what I was sure was a firecrest singing, I rushed downstairs to see this male in the holly tree by the kitchen window.
I had caught a glimpse of probably the same bird on Sunday; I then went out, and when I returned Greger said he had seen it again. He seemed a bit doubtful, though - said it definitely had the white eye stripe, but he couldn't see a crest. Amazingly, warning bells didn't ring....